Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Lactobacillus rhamnosus confers protection against colorectal cancer in rats

Jian Huang¹ , Dan Wang², Anye Zhang¹, Qinglian Zhong¹, Qun Huang¹

¹Department of Gastroenterology, The Eighth Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518033, Guangdong Province; ²Department of Anesthesiology, Ganzhou People's Hospital, The Ganzhou Hospital Affiliated to Nanchang University, Ganzhou 341000, Jiangxi Province, China.

For correspondence:- Jian Huang Email: BLeogour@yahoo.com

Accepted: 24 June 2019 Published: 28 July 2019

Citation: Huang J, Wang D, Zhang A, Zhong Q, Huang Q. Lactobacillus rhamnosus confers protection against colorectal cancer in rats. Trop J Pharm Res 2019; 18(7):1449-1454 doi: 10.4314/tjpr.v18i7.12

© 2019 The authors.
This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited..

Abstract

Purpose: To investigate the protective effect and mechanism of action of Lactobacillus rhamnosus against colorectal cancer (CRC).

Methods: A total of 40 healthy female Sprague Dawley rats weighing 100 – 140 g (mean weight = 120 ± 20 g) were used for this study. The rats were randomly assigned to four groups of 10 rats each: normal control group, L. rhamnosus group; 1, 2-dimethylhydrazine (DMH) group and treatment group. Rats in L. rhamnosus group were inoculated with L. rhamnosus (1 x 10⁸ CFU/mL) orally for 20 weeks, while rats in DMH group received 35 mg DMH/kg /week intraperitoneally for 10 weeks for induction of CRC. Treatment group rats received 35 mg DMH/kg bwt intraperitoneally for 10 weeks for induction of CRC, and were treated with L. rhamnosus (1 x 10⁸ CFU/mL) orally for 20 weeks. After 20 weeks, the rats were euthanized using ether anesthesia. expressions of inflammatory, angiogenesis and pro-apoptotic genes were determined using Western blotting and real-time quantitative polymerase chain reaction (qRT-PCR).

Results: Treatment with L. rhamnosus significantly reduced the incidence of CRC in the rats (p < 0.05). The incidence of multiple tumors in the treatment group was also significantly reduced, when compared to DMH group (p < 0.05). The protein expressions of inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), cyclooxygenase-2 (COX-2), bcl-2 and vascular endothelial growth factor α (VEGF-α) were significantly upregulated in DMH group, when compared with normal control group (p < 0.05). However, treatment with L. rhamnosus significantly down-regulated the expressions of these proteins (p < 0.05). DMH treatment also significantly upregulated the expressions of iNOS, TNF-α, VEGF-α, NF-kB, β-catenin and bax genes (p < 0.05). However, L. rhamnosus significantly reversed the effects of DMH on the expression levels of these genes (p < 0.05).

Conclusion: These results show that L. rhamnosus prevents CRC via suppression of expressions of inflammatory and angiogenesis genes, and upregulation of apoptotic gene expression.

Keywords: Colorectal cancer, Lactobacillus rhamnosus, Probiotics, Angiogenesis, expression